Marketable Securities (Tables)

6 Months Ended

Jun. 30, 2017

Investments Debt And Equity Securities [Abstract]

Schedule of Marketable Securities

	Market value		Cost basis		Unrealized losses, net
	(In millions)
December 31, 2016:
Current assets	$	4.4	$	4.4	$	—
Noncurrent assets:
The Amalgamated Sugar Company LLC	$	250.0	$	250.0	$	—
Other		3.5		3.7		(.2	)
Total	$	253.5	$	253.7	$	(.2	)
June 30, 2017:
Current assets	$	.8	$	.8	$	—
Noncurrent assets:
The Amalgamated Sugar Company LLC	$	250.0	$	250.0	$	—
Other		7.2		7.4		(.2	)
Total	$	257.2	$	257.4	$	(.2	)